To pass the test cases, the logic must handle both odd-numbered rows (1, 3, 5...) and even-numbered rows (2, 4, 6...) correctly. 1. The main() Function
If you only move left-to-right, you cannot create a checkerboard. Karel must turn around at the end of each row.
: Always verify Karel can move before attempting:
Before diving into the code, you must understand exactly what CodeHS requires for the v1 checkerboard. Karel starts at the bottom-left corner (Street 1, Avenue 1) facing East. Your program must paint the world in an alternating grid pattern. Key Constraints and Rules 916 checkerboard v1 codehs fixed
Using the same variable (like i ) for both loops. This causes the loops to crash into each other.
# Draw the square no_stroke() rect(col * square_size, row * square_size, square_size, square_size)
In the landscape of introductory computer science, few tools are as effective for teaching logic as the CodeHS graphics library. Among the classic exercises presented to students is the creation of a checkerboard—a seemingly simple visual pattern that actually requires a deep understanding of coordinate systems, iteration, and conditional logic. The "916 Checkerboard v1" assignment is a specific variation of this problem that often trips up beginners. A "fixed" version of this code does more than just produce a pretty picture; it demonstrates the fundamental shift from linear thinking to algorithmic problem-solving. To pass the test cases, the logic must
: If you are writing a custom print method, ensure your System.out.println(); sits outside the inner column loop but inside the outer row loop. Placing it incorrectly will cause your grid to print as a single vertical line.
Karel always starts facing East at (1,1) .
0 1 0 1 0 1 0 1 1 0 1 0 1 0 1 0 0 1 0 1 0 1 0 1 1 0 1 0 1 0 1 0 Use code with caution. Karel must turn around at the end of each row
Work regardless of the specific grid size defined in the scenario.
: This error usually means your if condition for the rows is wrong or you aren't actually assigning board[row][col] = 1 .
Set the (indices 0, 1, 2) and the bottom 3 rows (indices 5, 6, 7) to 1 s. Keep the middle 2 rows (indices 3, 4) as 0 s. Fixed Python Solution